Healthcare access is a fundamental tenet of positive health outcomes in wellness, prevention and chronic disease management, and together with quality care, can result in less disparate outcomes, and reduced healthcare delivery costs by preempting medical crises and severe outcomes. Although spotlighted in the current U.S. health policy agenda, improving financial access alone does not comprehensively address healthcare access. Affordability is one barrier to healthcare, but others such as availability and accessibiliy equally impact disparities in health and healthcare. The study of availability and accessibility considered together when measuring health service access is referred to as spatial access. Spatial access is particularly important for managing chronic diseases where regular visits and adherence to care practices can reduce severe outcomes. This proposal will contribute to the research on healthcare access through development and implementation of a framework for measuring, linking to outcomes, and evaluating interventions for spatial access. We will develop our framework and pilot the methods on one chronic respiratory condition, pediatric asthma, targeting children in the Medicaid system with a comparison across multiple states in the United States. We selected asthma because it is one of the most prevalent chronic childhood respiratory conditions, contributing to great losses in quality of life, costs, and morbidity. The proposed framework takes a system approach in modeling access and evaluating interventions, accounting for constraints in the system including mobility, user choice, willingness to travel, Medicaid eligibility and enrollment, congestion and capacity constraints. We apply this approach to quantify measures of spatial access across a large network of care. Using these measures, we further estimate the role that spatial access has on longitudinally observed outcomes while controlling for potentially contributing factors to severe outcomes, using advanced statistical methods. The aim of the modeling and inference on spatial access is to identify interventions for reducing severe outcomes while increasing accessibility and availability of care. Using optimization methods, we evaluate interventions by effectively allocating resources to areas in need of care for asthma under budget constraints. The intervention models build on the system model for estimating spatial access and on the statistical models for projecting the impact of access intervention on reducing severe health outcomes.